Handpiece and blade configurations for ultrasonic surgical instrument

Abstract

A surgical apparatus comprises a body, an ultrasonic transducer, a shaft, and an end effector. The ultrasonic transducer is operable to convert electrical power into ultrasonic vibrations. The body comprises a pivotal trigger. The shaft couples the end effector and the body together. The end effector comprises a clamp arm and an ultrasonic blade in acoustic communication with the ultrasonic transducer. The ultrasonic blade is operable to deliver ultrasonic vibrations to tissue. Pivotal movement of the trigger causes movement of the clamp arm. The trigger includes a compliant feature configured to limit the amount of force delivered to tissue by the clamp arm. The flexible feature may comprise a flexible band, living hinge, a series of living hinges, or a flexible tab.

I/we claim: 
     
         1 . An apparatus for operating on tissue, the apparatus comprising:
 (a) a handle assembly;   (b) a shaft assembly extending distally from the handle assembly, wherein the shaft assembly defines a longitudinal axis;   (c) an end effector comprising a pivotable clamp arm and an active element; and   (d) a trigger, wherein the trigger is pivotably coupled with the body, wherein the trigger is configured to move pivotably toward and away from the handle assembly, the trigger is pivotable to cause pivotal movement of the clamp arm relative to the active element, and wherein the trigger comprises at least one compliant feature configured to deform upon experiencing a predetermined amount of force, wherein the at least one complaint feature is configured to restrict transfer of force from the trigger to the clamp arm.   
     
     
         2 . The apparatus of  claim 1 , wherein the trigger is pivotable about an axis located above the shaft assembly. 
     
     
         3 . The apparatus of  claim 1 , wherein the trigger is operable to pivot away from the handle assembly to cause the clamp arm to move away from the active element. 
     
     
         4 . The apparatus of  claim 1 , wherein a resilient member biases the trigger away from the handle assembly. 
     
     
         5 . The apparatus of  claim 4 , wherein the resilient member comprises at least one spring. 
     
     
         6 . The apparatus of  claim 1 , wherein the at least one compliant feature is configured to transition between a substantially straight configuration and a bent configuration, wherein the at least one complaint feature is configured to maintain the straight configuration until experiencing the predetermined amount of force. 
     
     
         7 . The apparatus of  claim 1 , wherein the at least one compliant feature comprises a flexible band. 
     
     
         8 . The apparatus of  claim 1 , wherein the at least one compliant feature comprises at least one living hinge. 
     
     
         9 . The apparatus of  claim 8 , wherein the at least one living hinge comprises at least a first living hinge and a second living hinge. 
     
     
         10 . The apparatus of  claim 9 , wherein the first living hinge is configured to plastically deform in response to a first predetermined amount of force, and wherein the second living hinge is configured to plastically deform in response to a second predetermined amount of force. 
     
     
         11 . The apparatus of  claim 9 , wherein the trigger further comprises a stiffening member. 
     
     
         12 . The apparatus of  claim 11 , wherein the stiffening member is configured to limit deformation of one or both of the first living hinge or the second living hinge. 
     
     
         13 . The apparatus of  claim 1 , wherein the handle assembly further comprises trigger limiting feature, wherein the trigger limiting feature is configured to restrict pivotal movement of the trigger. 
     
     
         14 . The apparatus of  claim 13 , wherein the trigger limiting feature is adjustable. 
     
     
         15 . The apparatus of  claim 1 , wherein the active element comprises an ultrasonic blade. 
     
     
         16 . The apparatus of  claim 1 , wherein the handle assembly comprises a pistol grip. 
     
     
         17 . An apparatus for operating on tissue, the apparatus comprising:
 (a) a handle assembly;   (b) a shaft assembly extending distally from the handle assembly, wherein the shaft assembly defines a longitudinal axis;   (c) an end effector comprising a pivotable clamp arm and an active element, wherein the clamp arm is pivotably coupled with a distal end of the shaft assembly; and   (d) a trigger, wherein the trigger is pivotably coupled with the body, wherein the trigger is pivotable about an axis located above the shaft assembly, wherein the trigger is configured to pivot between a first position and a second position, wherein the trigger is operable to cause pivotal movement of the clamp arm in response to pivoting of the trigger between the first position and the second position.   
     
     
         18 . The apparatus of  claim 17 , wherein the trigger is pivotably coupled with a proximal end of the shaft assembly. 
     
     
         19 . An apparatus for operating on tissue, the apparatus comprising:
 (a) a handle assembly;   (b) an ultrasonic transducer operable to convert electrical power into ultrasonic vibrations;   (c) a shaft assembly extending distally from the handle assembly, wherein the shaft defines a longitudinal axis;   (d) an end effector comprising a pivotable clamp arm and an ultrasonic blade in acoustic communication with the ultrasonic transducer via a waveguide, wherein the ultrasonic blade comprises:
 (i) a first relief formed in the ultrasonic blade and extending in a first direction, and 
 (ii) a second relief formed in the ultrasonic blade and extending in a second direction. 
   
     
     
         20 . The apparatus of  claim 19 . wherein one or both of the first relief or the second relief pass through at least two surfaces of the ultrasonic blade.